Bearing and/or seal assembly including permeable body with features engineered to form a desired distribution pattern for a pressurized gas conveyed therethrough
A bearing and/or seal assembly where pressurized gas (e.g., air) may be arranged to produce a contact-free bearing and/or seal is provided. The assembly includes a permeable body ( 12 ) including structural features ( 13 ) selectively engineered to convey a pressurized gas (Ps) from an inlet side ( 20 ) side of the permeable body to an outlet side ( 22 ) of the permeable body to form an annular film of the pressurized gas relative to the rotatable shaft. Disclosed embodiments may be produced by way of three-dimensional (3D) Printing/Additive Manufacturing (AM) technologies with practically no manufacturing variability; and may also cost-effectively and reliably benefit from the relatively complex geometries and the features and/or conduits that may be involved to, for example, form the desired distribution pattern or impart a desired directionality to the pressurized gas conveyed through the permeable body of the bearing and/or seal assembly.
1. A bearing and/or seal assembly comprising:
a rotatable shaft ( 14 );
an annular housing ( 16 ) disposed concentric to the rotatable shaft and defining an annular cavity ( 18 ) about the rotatable shaft; and
a permeable body ( 12 ) supported by the annular housing, the permeable body
based on structural features ( 13 ) selectively engineered to convey a pressurized gas (Ps) from an inlet side ( 20 ) disposed at a radially-outward side of the permeable body to an outlet side ( 22 ) disposed at a radially-inward side of the permeable body to form an annular film of the pressurized gas relative to the rotatable shaft, wherein a desired distribution pattern of the pressurized gas is formed based on the selectively engineered structural features, wherein the structural features are selectively engineered to form conduits ( 31 ) non-uniformly distributed along a longitudinal axis ( 32 ) and/or about a circumferential axis ( 37 ) of the permeable body for selectively controlling the spatial density of jets of the pressurized gas conveyed through the permeable body ( 12 ).
2. The bearing and/or seal assembly of claim 1 , wherein the permeable body ( 12 ) comprises an additively manufactured structure.
3. The bearing and/or seal assembly of claim 1 , wherein the structural features are selectively engineered to form a lattice ( 24 ) of structural features within the permeable body.
4. The bearing and/or seal assembly of claim 1 , wherein the structural features are selectively engineered to form a metal foam structure comprising open cells ( 26 ) within the permeable body.
5. The bearing and/or seal assembly of claim 4 , wherein the open cells ( 23 1 , 26 2 , 26 3 ) of the metal foam structure are engineered to provide a varying porosity between the inlet side ( 20 ) and the outlet side ( 22 ) of the permeable body.
6. The bearing and/or seal assembly of claim 1 , wherein the structural features are selectively engineered to form conduits ( 30 ) uniformly distributed along a longitudinal axis ( 32 ) and/or about a circumferential axis ( 37 ) of the permeable body.
7. The bearing and/or seal assembly of claim 1 , further comprising a damping cavity ( 40 ) in fluid communication with the annular cavity ( 18 ).
8. The bearing and/or seal assembly of claim 7 , wherein a side ( 42 ) of the damping cavity in fluid communication with the annular cavity is defined by a gapped structure ( 44 ).
9. The bearing and/or seal assembly of claim 7 , wherein the damping cavity ( 40 ) is further in fluid communication with the inlet side ( 20 ) of the permeable body to receive pressurized gas from the inlet side of the permeable body.
10. The bearing and/or seal assembly of claim 1 , wherein the permeable body comprises a plurality of sections ( 12 1 , 12 2 , 12 3 , 12 4 ) integral with one another, wherein the structural features in at least some sections of the plurality of sections are engineered to form desired distribution patterns of the pressurized gas along a longitudinal axis and/or a circumferential axis of the permeable body.
11. The bearing and/or seal assembly of claim 10 , wherein at least a first section ( 12 1 ) of the plurality of sections comprises structural features selectively engineered to form conduits ( 30 ) uniformly distributed along the longitudinal axis and/or about the circumferential axis of the permeable body.
12. The bearing and/or seal assembly of claim 10 , wherein at least a second section ( 12 2 ) of the plurality of sections comprises structural features selectively engineered to form conduits ( 31 ) non-uniformly distributed along the longitudinal axis and/or about the circumferential axis of the permeable body.
13. The bearing and/or seal assembly of claim 10 , wherein at least a third section ( 12 3 ) of the plurality of sections comprises structural features selectively engineered to form segment conduits ( 35 ) including 1) a conduit segment ( 35 ′) having a radial-axial tilt disposed upstream of the outlet side ( 22 ) of the permeable body, the radial-axial tilt of the conduit segment arranged to jet the pressurized gas in a direction effective to offset an axial fluidic load that develops during rotation of the shaft; and/or
further including 2) a conduit segment ( 35 ″) having a radial-circumferential tilt disposed upstream of the outlet side ( 22 ) of the permeable body, the radial-circumferential tilt of
the conduit segment arranged to jet the pressurized gas in a direction effective to offset a circumferential fluidic load that develops during rotation of the shaft.
14. The bearing and/or seal assembly of claim 10 , wherein at least one section ( 12 4 ) of the plurality of sections comprises a damping cavity ( 40 ) in fluid communication with the annular cavity ( 18 ) through a gapped structure ( 44 ).
15. The bearing and/or seal assembly of claim 14 , wherein the damping cavity ( 40 ) is further in fluid communication with the inlet side ( 20 ) of the permeable body to receive pressurized gas from the inlet side of the permeable body.
16. The bearing and/or seal assembly of claim 1 , wherein the permeable body comprises a material selected from the group consisting of graphite, carbon, silicon carbide, tungsten carbide, alumina, titanium, Inconel, Babbitt metal, a ceramic-based material, a carbon fiber-epoxy composite material and a combination of two or more of said materials.
17. The bearing and/or seal assembly of claim 1 , further comprising a permeable body ( 12 ′) supported by a housing ( 16 ′) disposed at an axial end of rotatable shaft 14 , wherein structural features ( 13 ′) within permeable body ( 12 ′) are selectively engineered to convey pressurized gas from an inlet side ( 52 ) disposed at an axially-outward side of permeable body ( 12 )′ to an outlet side ( 54 ) disposed at an axially-inward side of permeable body ( 12 ′) to form an annular film of pressurized gas arranged to act on a collar 56 of rotatable shaft 14 .
18. A bearing and/or seal assembly comprising:
a rotatable shaft ( 14 );
an annular housing ( 16 ) disposed concentric to the rotatable shaft and defining an annular cavity ( 18 ) about the rotatable shaft; and
a permeable body ( 12 ) supported by the annular housing, the permeable body
based on structural features ( 13 ) selectively engineered to convey a pressurized gas (Ps) from an inlet side ( 20 ) disposed at a radially-outward side of the permeable body to an outlet side ( 22 ) disposed at a radially-inward side of the permeable body to form an annular film of the pressurized gas relative to the rotatable shaft, wherein a desired distribution pattern of the pressurized gas is formed based on the selectively engineered structural features; and
wherein the structural features are selectively engineered to form conduits ( 35 ) including 1) a conduit segment ( 35 ′) having a radial-axial tilt disposed upstream of the outlet side ( 22 ) of the permeable body, the radial-axial tilt of the conduit segment arranged to jet the pressurized gas in a direction effective to offset an axial fluidic load ( 36 ) that develops during rotation of the shaft; and/or further including 2) a conduit segment ( 35 ″) having a radial-circumferential tilt disposed upstream of the outlet side ( 22 ) of the permeable body, the radial-circumferential tilt of the conduit segment arranged to jet the pressurized gas in a direction effective to offset a circumferential fluidic load ( 36 ′) that develops during rotation of the shaft.